Dynamic load regulation method for transmission line of high-voltage transmission system

Abstract

The application relates to the technical field of power transmission line load regulation, in particular to a power transmission line dynamic load regulation method suitable for a high-voltage power transmission system, which comprises the following steps: collecting current signals of a power transmission line of an oilfield power distribution and transmission network at each moment; determining fluctuation coefficients of the power transmission line current load at each moment; acquiring the frequency of the oilfield high-voltage power transmission system at each moment and taking the frequency as the center frequency of a Butterworth filter at each moment; determining the order of the Butterworth filter at each moment according to the numerical value of the fluctuation coefficient, and optimizing the Butterworth filter by combining the center frequency and the order; extracting harmonics of the current signals at each moment by using the optimized Butterworth filter, and compensating the current based on the harmonic components. The application improves the precision of power transmission line load regulation.

Description

Technical Field

[0001] This application relates to the field of power transmission line load regulation technology, specifically to a dynamic load regulation method for power transmission lines applicable to high-voltage power transmission systems. Background Technology

[0002] As the scale of oil and gas exploration and production in oilfields continues to expand, the high-voltage power supply radius and coverage of the oilfield power distribution and transmission network are also constantly expanding. The distribution of high-voltage power lines is intricate and complex, and oilfields have higher requirements for power demand and power quality.

[0003] The oilfield's power distribution network connects numerous pumping units, water injection pumps, and oil stations with fluctuating loads, accounting for over 90% of the total electricity consumption. The operation of the pumping unit group exhibits regular pulsations, and simultaneously, to maintain stable formation pressure, the oilfield operates multiple high-power water injection pumps. To improve the stability and safety of the oilfield's pumping units, frequency converters are installed on the load side of the well transformers to drive the pumping units, as frequency converter-driven pumping units have relatively low energy consumption. However, frequency converters are nonlinear devices with complex harmonic spectra, making it difficult for conventional filters to effectively suppress harmonic generation. Furthermore, the electromagnetic interference generated by harmonics can affect other interference protection devices in the oilfield's power system, causing malfunctions, which in turn interfere with load regulation of transmission lines. This makes it difficult to ensure stable and safe power transmission under changing loads and complex supply and demand environments, reducing the stability and reliability of the power grid. Summary of the Invention

[0004] To address the aforementioned technical problems, this application provides a dynamic load control method for transmission lines applicable to high-voltage transmission systems, thereby resolving the existing issues.

[0005] The dynamic load control method for transmission lines applicable to high-voltage transmission systems in this application adopts the following technical solution: One embodiment of this application provides a method for dynamic load control of transmission lines in high-voltage transmission systems, the method comprising the following steps: Collect current signals of transmission lines in the oilfield power distribution network at various times; In the collected current signals, the numerical and temporal differences between the nearest extreme value and the nearest range of each adjacent time point are analyzed to determine the fluctuation coefficient of the transmission line current load at each time point. The differences in the effective current values ​​at each time point and those of its neighboring time points are analyzed to determine the angular frequency of the power grid at each time point. The frequency of the oilfield high-voltage transmission system at each time point is determined by combining the angular frequency with the fluctuation coefficient, and this frequency is used as the center frequency of the Butterworth filter at each time point. By using the magnitude of the fluctuation coefficient, the order of the Butterworth filter at each time point is determined, and the Butterworth filter is optimized by combining the center frequency and the order. The optimized Butterworth filter is used to extract harmonics from the current signal at each time step, and current compensation is performed based on the harmonic components.

[0006] In one embodiment, determining the volatility coefficient includes: For any given moment, the nearest maximum value in the current signal is obtained and recorded as the first maximum value. The nearest maximum value in the current signal to the nearest neighboring moment is obtained and recorded as the second maximum value. Calculate the numerical difference and time difference between the first maximum and the second maximum; Accordingly, the minimum value closest to any given moment is obtained from the current signal and denoted as the first minimum value; the minimum value closest to the nearest moment to any given moment is obtained from the current signal and denoted as the second minimum value. Calculate the numerical difference and time difference between the first minimum and the second minimum; The numerical difference between the first maximum and the second maximum is weighted based on the time difference between the first maximum and the second maximum to obtain a first weighted result; The numerical difference between the first minimum and the second minimum is weighted based on the time difference between the first minimum and the second minimum to obtain a second weighted result; The volatility coefficient is positively correlated with both the first weighted result and the second weighted result.

[0007] In one embodiment, the sum of a first weighted result and a second weighted result is calculated, wherein the fluctuation coefficient is the mean of the sums of all neighboring times at any given time.

[0008] In one embodiment, calculating the numerical difference and time difference between the first maximum and the second maximum includes: Calculate the absolute value of the difference between the first maximum and the second maximum as the numerical difference, and calculate the absolute value of the difference between the corresponding time of the first maximum and the corresponding time of the second maximum as the time difference.

[0009] In one embodiment, determining the angular frequency of the power grid at each moment includes: The sum of the effective current values ​​of a predetermined number of neighboring times before each time point is calculated. Based on the sum of the effective current values ​​at each time point and the effective current values ​​at each time point, the angular frequency of the power grid at each time point is determined.

[0010] In one embodiment, the expression for the angular frequency of the power grid at each moment is: In the formula, The effective value of the current at time t-1 The effective value of the current at time t-2. Let be the effective value of the current at time t. Let ω be the angular frequency of the power grid at time t, and cos() be the trigonometric cosine function. The sum is the cumulative sum.

[0011] In one embodiment, the frequency of the oilfield high-voltage transmission system at each time point is positively correlated with the angular frequency and negatively correlated with the fluctuation coefficient.

[0012] In one embodiment, the expression for the frequency of the oilfield high-voltage transmission system at each time point is: In the formula, Let t be the frequency of the oilfield's high-voltage power transmission system. Let be the fluctuation coefficient of the transmission line current load at time t. Let be the angular frequency of the power grid at time t. Pi is the mathematical constant of a circle.

[0013] In one embodiment, determining the order of the Butterworth filter at each time step using the magnitude of the fluctuation coefficient includes: If the fluctuation coefficient is greater than or equal to a preset threshold, the order of the Butterworth filter is set to a first value; otherwise, the order of the Butterworth filter is set to a second value, wherein the first value is greater than the second value.

[0014] In one embodiment, the current compensation based on harmonic components includes: At each time point, a compensation current with equal amplitude but opposite phase to the extracted harmonic current components is input into the power grid based on pulse width modulation technology to complete the current compensation.

[0015] This application has at least the following beneficial effects: This application determines the fluctuation coefficient of the transmission line current load at each moment by analyzing the numerical and temporal differences between the nearest extreme value and the nearest range of adjacent moments in the collected current signal. The determination of the fluctuation coefficient quantifies the degree of current load fluctuation, helps identify transient changes and abnormal fluctuations in the load, improves the response speed of the high-voltage transmission system to unstable conditions, and enhances the accuracy of load regulation. Analyzing the difference in the effective current value between each moment and its adjacent moments determines the angular frequency of the power grid at each moment, which helps to capture the power grid frequency deviation in real time and improves frequency stability. Combining the angular frequency and the fluctuation coefficient, the frequency of the oilfield high-voltage transmission system at each moment is determined and used as the center frequency of the Butterworth filter at each moment, ensuring that the Butterworth filter can be optimized for the current power grid state and dynamically adjust the center frequency during frequency fluctuations to prevent harmonic amplification or distortion. Using the magnitude of the fluctuation coefficient, the order of the Butterworth filter at each moment is determined, combined with the... The center frequency and order are used to optimize the Butterworth filter. Dynamically setting the center frequency allows the Butterworth filter to adapt to changes in the power grid, improving the targeting and efficiency of harmonic extraction. Dynamically selecting the order based on the fluctuation coefficient enhances the frequency selectivity of the Butterworth filter. Higher-order filters provide steeper filtering characteristics during periods of severe fluctuation, while lower-order filters reduce computational burden under stable conditions. The optimized Butterworth filter is used to extract harmonics from the current signal at various times, and current compensation is performed based on the harmonic components. The optimized Butterworth filter significantly improves filtering performance and dynamic response characteristics, increases the accuracy of harmonic separation, reduces signal loss, enhances the robustness of the high-voltage transmission system to load surges, avoids the shortcomings of traditional fixed-parameter filters, and directly performs current compensation based on harmonic extraction from the optimized filter, improving the accuracy of load regulation, significantly improving power quality, enhancing the load capacity and voltage stability of transmission lines, reducing voltage fluctuations and distortion, and ensuring the purity of power supply. Attached Figure Description

[0016] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A flowchart illustrating the steps of a dynamic load control method for transmission lines applicable to high-voltage transmission systems provided in this application; Figure 2 This is a flowchart showing the relationship between current compensation indicators. Detailed Implementation

[0018] To further illustrate the technical means and effects adopted by this application to achieve the intended purpose of the invention, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of the dynamic load control method for transmission lines applicable to high-voltage transmission systems proposed in this application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0020] The following description, in conjunction with the accompanying drawings, details the specific scheme of the dynamic load control method for transmission lines applicable to high-voltage transmission systems provided in this application.

[0021] This application provides an embodiment of a dynamic load control method for transmission lines in high-voltage transmission systems. Specifically, the method is described below. Please refer to [link to relevant documentation]. Figure 1 The method includes the following steps: Step S001: Collect the current signals of the transmission lines of the oilfield power distribution network at various times.

[0022] Oilfield power distribution and transmission networks differ from ordinary power grids, possessing certain unique characteristics. Typically, oilfield power distribution and transmission lines are located in relatively remote geological locations, with long power supply radii, complex equipment, and harsh operating environments. This embodiment utilizes an automatic oilfield information acquisition system to obtain current signals from the transmission lines of the oilfield power distribution and transmission network at various times. The acquisition frequency is 500Hz, but implementers can set it according to actual conditions; this embodiment does not impose any restrictions. The automatic oilfield information acquisition system is a well-known existing technology, and its specific process will not be elaborated upon.

[0023] Step S002: In the collected current signal, analyze the numerical and temporal differences between the nearest extreme value at each time and the nearest range at the nearest adjacent time, and determine the fluctuation coefficient of the transmission line current load at each time.

[0024] In oilfield power distribution networks, the operation of pumping units on the load side generates harmonic pollution. Harmonic suppression typically employs active and passive harmonic suppression technologies. Passive harmonic suppression uses external harmonic filtering equipment to absorb harmonic currents. Currently, APF (Active Power Filter) technology is widely used in oilfield power grid transmission lines to filter out harmonic oscillations generated during pumping unit operation. However, APF requires real-time and accurate acquisition of harmonic and reactive current data in the power grid to control the oilfield power distribution transmission lines.

[0025] The oil pumping unit uses a motor to drive a crankshaft in a reciprocating motion, causing the pumping head to move up and down, bringing underground oil to the surface. During the pumping head's ascent and start-up, the motor drives the pumping action; however, during the pumping head's descent, the load lightens, and the motor is essentially in a free state. At this time, the pumping unit is in reverse power generation mode, transmitting electrical energy back to the grid via a frequency converter. Due to its nonlinear characteristics, the current load curve of the oilfield's power distribution and transmission lines becomes distorted, which can significantly affect and interfere with the normal operation of other equipment in the oilfield's power distribution and transmission network.

[0026] In a power system, if there is no nonlinear load, the current signal of the transmission line should be in the form of a sinusoidal current. However, due to the presence of nonlinear loads in the power system, the harmonic current signal will be superimposed on the fundamental current signal to form the current signal that the power grid is actually operating. In order to analyze the degree of harmonic current interference on the current signal collected in this embodiment, this embodiment first applies a window to the collected current signal. Since the stroke cycle of the pumping unit is usually 12-15 seconds, this embodiment sets the length of the windowing time window to 12 seconds. Implementers can set it according to the actual situation, and this embodiment does not impose any restrictions on it.

[0027] Secondly, the fluctuation coefficient of the transmission line current load at each time point is calculated, specifically: For any given moment, the nearest maximum value in the current signal is obtained and recorded as the first maximum value. The nearest maximum value in the current signal to the nearest neighboring moment is obtained and recorded as the second maximum value. Calculate the numerical difference and time difference between the first maximum and the second maximum; Accordingly, the minimum value closest to any given moment is obtained from the current signal and denoted as the first minimum value; the minimum value closest to the nearest moment to any given moment is obtained from the current signal and denoted as the second minimum value. Calculate the numerical difference and time difference between the first minimum and the second minimum; The numerical difference between the first maximum and the second maximum is weighted based on the time difference between the first maximum and the second maximum to obtain a first weighted result; The numerical difference between the first minimum and the second minimum is weighted based on the time difference between the first minimum and the second minimum to obtain a second weighted result; The volatility coefficient is positively correlated with both the first weighted result and the second weighted result.

[0028] It should be noted that the difference represents the degree of difference between two variables, and can be calculated using methods such as the absolute value of the difference, the square of the difference, or the ratio. This embodiment does not impose any restrictions on this.

[0029] The expression for the fluctuation coefficient of the transmission line current load at each moment in this embodiment is as follows: In the formula, Let be the fluctuation coefficient of the transmission line current load at time t. The number of neighboring times at time t is defined in this embodiment. The n times before time t are considered as neighboring times at time t, where n=3. Implementers can set this number according to their actual situation, and this embodiment does not impose any restrictions on it. Let t be the time difference between the first maximum and the second maximum corresponding to time t and its i-th neighboring time. Let be the absolute value of the difference between the first maximum and the second maximum at time t and its i-th neighboring time. Let be the time difference between the first minimum and the second minimum at time t and its i-th neighboring time. Let t be the absolute value of the difference between the first minimum and the second minimum corresponding to time t and its i-th neighboring time.

[0030] In this embodiment The calculation method is as follows: Calculate the absolute value of the difference between the corresponding time of the first maximum and the corresponding time of the second maximum at time t and its i-th neighboring time, denoted as the absolute value of the time difference. Then, use the ratio of this absolute value of the time difference to the length of a set time window as the time difference between the first maximum and the second maximum at time t and its i-th neighboring time. Correspondingly, for... The calculation method is based on the first and second minimum values, and adopts the same approach as... Using the same calculation method, the time difference between the first minimum and the second minimum corresponding to time t and its i-th neighboring time is obtained.

[0031] It should be understood that by calculating the fluctuation coefficient, the changes in current load at different times during the operation of the pumping unit can be analyzed. If the current waveform of the transmission line is normal and undistorted, the difference between the calculated maximum and minimum values ​​at different sampling points should be relatively small. Conversely, if the power system experiences harmonic distortion due to nonlinear loads, and the harmonic frequency is an integer multiple of the fundamental frequency, the difference in extreme values ​​at different sampling points in the current signal will be larger than the difference in extreme values ​​of an undistorted current waveform. If the difference in extreme values ​​at different sampling points is too large within one stroke cycle during the operation of the pumping unit, it indicates a more severe distortion of the current waveform, and the calculated fluctuation coefficient value of the transmission line current load will also be relatively large.

[0032] Step S003: Analyze the difference in the effective current value between each time moment and its neighboring time moments to determine the angular frequency of the power grid at each time moment; combine the angular frequency with the fluctuation coefficient to determine the frequency of the oilfield high-voltage transmission system at each time moment, and use it as the center frequency of the Butterworth filter at each time moment.

[0033] Variable frequency pumping units, acting as nonlinear loads, generate components that are integer multiples of the fundamental frequency in the power grid. Therefore, in the process of active power filters filtering out harmonics from transmission line loads, real-time and accurate acquisition of harmonics is a crucial prerequisite for harmonic suppression during transmission line load regulation. The theory of three-phase instantaneous reactive power detection is based on average power. Currently, based on the theory of three-phase instantaneous reactive power, pq and [other parameters] are commonly used. This method obtains the DC component through an LPF low-pass filter, and then uses the difference between the DC component and the original three-phase current in a transformed coordinate system to obtain the harmonic components. In practical applications, Butterworth low-pass filters are often used, but the order and center frequency of the Butterworth low-pass filter play a crucial role in harmonic component extraction. The order determines the attenuation rate of the filter; a higher order results in a narrower transition band, enabling more accurate separation of the fundamental frequency signal and harmonics, especially when the harmonics are close to the fundamental frequency. Higher-order filters are more effective in removing higher-order harmonics and noise, but increase computational complexity and delay. The center frequency determines the frequency at which the filter begins to attenuate the signal. An accurate center frequency setting ensures effective extraction of the desired low-frequency signal while removing unwanted high-frequency components. An improper center frequency setting may lead to signal loss or inaccurate harmonic extraction. In other words, the accurate selection of the Butterworth low-pass filter's order and center frequency directly affects the accuracy and efficiency of harmonic component extraction.

[0034] Therefore, in order to ensure the safety of load regulation of the high-voltage power transmission system in the oilfield, this embodiment combines the load variation law of the oilfield pumping unit to design the optimal Butterworth filter, thereby realizing the detection and filtering of harmonic components of the oilfield power transmission line.

[0035] Typically, the fundamental frequency provided by the power grid is f=50Hz, at which point the effective value of the current signal is... , It is the angular frequency, that is Because the high-voltage power transmission system in the oilfield contains a large number of nonlinear loads, there are numerous high-order and low-order harmonics in the oilfield power grid, resulting in significant variations in the grid frequency acquired by the transmission lines. Therefore, this embodiment calculates the grid frequency of the oilfield high-voltage transmission system at various times to track and calculate the grid frequency of the oilfield high-voltage transmission system. Specifically: First, the sum of the effective current values ​​of a preset number of adjacent times is calculated. Based on the sum of the effective current values ​​at each time and the effective current values ​​at each time, the angular frequency of the power grid at each time is determined. In this embodiment, the preset number is set to 2. Implementers can set it according to the actual situation. This embodiment does not limit it.

[0036] The angular frequency of the power grid at each moment is calculated as follows: In the formula, The effective value of the current at time t-1 The effective value of the current at time t-2. Let be the effective value of the current at time t. Let ω be the angular frequency of the power grid at time t, and cos() be the trigonometric cosine function. The sum is the cumulative sum.

[0037] Secondly, the frequency of the oilfield high-voltage transmission system at each moment is positively correlated with the angular frequency and negatively correlated with the fluctuation coefficient. The expression for the frequency of the oilfield high-voltage transmission system at each moment is as follows: In the formula, Let t be the frequency of the oilfield's high-voltage power transmission system. Let be the fluctuation coefficient of the transmission line current load at time t. Let be the angular frequency of the power grid at time t. Pi is the mathematical constant of a circle.

[0038] Because there are a large number of nonlinear loads in the high-voltage power transmission system of the oilfield, a large number of harmonics are superimposed, so the real-time frequency of the power grid will change. In order to accurately obtain the power grid frequency under the nonlinear load operating state, this embodiment uses the current fluctuation caused by the operation of the oilfield pumping unit to perform real-time tracking calculation of the power grid frequency, thereby obtaining the real-time frequency of the power transmission system.

[0039] At time t, the frequency of the oilfield high-voltage transmission system will be... As the center frequency of the Butterworth filter.

[0040] Step S004: Using the magnitude of the fluctuation coefficient, determine the order of the Butterworth filter at each moment. Combine the center frequency with the order to optimize the Butterworth filter. Use the optimized Butterworth filter to extract harmonics from the current signal at each moment and perform current compensation based on the harmonic components.

[0041] Furthermore, the order of the Butterworth filter determines the real-time accuracy of harmonic detection and filtering in transmission lines. A higher order Butterworth filter generally results in higher accuracy in harmonic filtering, but it cannot achieve precise tracking, detection, and calculation of grid harmonic components. This embodiment dynamically adjusts the Butterworth filter order based on the fluctuation coefficient of the transmission line current load. A larger fluctuation coefficient indicates more significant fluctuations caused by the grid's nonlinear load. In this case, to enhance the accuracy of harmonic detection, a higher order should be set for the Butterworth filter. Therefore, this embodiment presets a threshold T. When the fluctuation coefficient of the transmission line current load at time t is greater than or equal to the threshold T, it indicates significant fluctuations caused by the grid's nonlinear load. In this case, to reduce harmonic detection errors, the order of the Butterworth filter is set to a first value, N1. Otherwise, if the fluctuation coefficient of the transmission line current load at time t is less than the threshold T, it indicates a good load condition. In this case, to ensure real-time tracking of the grid load, the order of the Butterworth filter is set to a second value, N2. The first value N1 is greater than the second value N2. By dynamically adjusting the order of the Butterworth filter, the Butterworth filter is optimized, thereby enabling real-time and accurate tracking of harmonic components in the load of the power grid transmission line.

[0042] In this embodiment, T=0.7, N1=4, and N2=2 are set. Implementers can set these values ​​according to their actual situation, and this embodiment does not impose any restrictions on them.

[0043] For the current signal at time t, a current signal within a time window is taken forward. An optimized Butterworth filter is used to extract harmonic components from this current signal. A PWM (Pulse-width Modulation) converter is then used to input a compensation current into the power grid with the same amplitude but opposite phase to the detected harmonic current components. This cancels out the interference of harmonic current components on the safety of power grid operation, achieving dynamic load control of high-voltage transmission lines. The flowchart of the current compensation index relationship is as follows: Figure 2 As shown.

[0044] It should be noted that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, specific embodiments of this specification have been described above. Additionally, the processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired results. In some implementations, multitasking and parallel processing are possible or may be advantageous.

[0045] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0046] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them; modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions of some of the technical features, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for dynamic load control of transmission lines applicable to high-voltage transmission systems, characterized in that, The method includes the following steps: Collect current signals of transmission lines in the oilfield power distribution network at various times; In the collected current signals, the numerical and temporal differences between the nearest extreme value and the nearest range of each adjacent time point are analyzed to determine the fluctuation coefficient of the transmission line current load at each time point. The differences in the effective current values ​​at each time point and those of its neighboring time points are analyzed to determine the angular frequency of the power grid at each time point. The frequency of the oilfield high-voltage transmission system at each time point is determined by combining the angular frequency with the fluctuation coefficient, and this frequency is used as the center frequency of the Butterworth filter at each time point. By using the magnitude of the fluctuation coefficient, the order of the Butterworth filter at each time point is determined, and the Butterworth filter is optimized by combining the center frequency and the order. The optimized Butterworth filter is used to extract harmonics from the current signal at each time step, and current compensation is performed based on the harmonic components. Determining the angular frequency of the power grid at each moment includes: calculating the sum of the effective current values ​​of a preset number of adjacent moments before each moment, and determining the angular frequency of the power grid at each moment based on the sum of the current values ​​at each moment and the effective current values ​​at each moment. The determination of the fluctuation coefficient includes: for any given moment, obtaining the nearest maximum value in the current signal, denoted as the first maximum value; obtaining the nearest maximum value in the current signal to a neighboring moment, denoted as the second maximum value; calculating the numerical difference and time difference between the first maximum value and the second maximum value; correspondingly, obtaining the nearest minimum value in the current signal, denoted as the first minimum value; obtaining the nearest minimum value in the current signal to a neighboring moment, denoted as the second minimum value; calculating the numerical difference and time difference between the first minimum value and the second minimum value; weighting the numerical difference between the first maximum value and the second maximum value based on the time difference to obtain a first weighted result; weighting the numerical difference between the first minimum value and the second minimum value based on the time difference to obtain a second weighted result; the fluctuation coefficient is positively correlated with both the first weighted result and the second weighted result.

2. The dynamic load control method for transmission lines applicable to high-voltage transmission systems as described in claim 1, characterized in that, The sum of the first weighted result and the second weighted result is calculated, and the fluctuation coefficient is the mean of the sums of all neighboring times at any given time.

3. The dynamic load control method for transmission lines applicable to high-voltage transmission systems as described in claim 1, characterized in that, The calculation of the numerical difference and time difference between the first maximum and the second maximum includes: Calculate the absolute value of the difference between the first maximum and the second maximum as the numerical difference, and calculate the absolute value of the difference between the corresponding time of the first maximum and the corresponding time of the second maximum as the time difference.

4. The dynamic load control method for transmission lines applicable to high-voltage transmission systems as described in claim 1, characterized in that, The expression for the angular frequency of the power grid at each moment is: In the formula, The effective value of the current at time t-1 The effective value of the current at time t-2. Let be the effective value of the current at time t. Let ω be the angular frequency of the power grid at time t, and cos() be the trigonometric cosine function. The sum is the cumulative sum.

5. The dynamic load control method for transmission lines applicable to high-voltage transmission systems as described in claim 1, characterized in that, The frequency of the oilfield high-voltage power transmission system at each time point is positively correlated with the angular frequency and negatively correlated with the fluctuation coefficient.

6. The dynamic load control method for transmission lines applicable to high-voltage transmission systems as described in claim 1, characterized in that, The expression for the frequency of the oilfield high-voltage transmission system at each time point is: In the formula, Let t be the frequency of the oilfield's high-voltage power transmission system. Let be the fluctuation coefficient of the transmission line current load at time t. Let be the angular frequency of the power grid at time t. Pi is the mathematical constant of a circle.

7. The method for dynamic load control of transmission lines applicable to high-voltage transmission systems as described in claim 1, characterized in that, Determining the order of the Butterworth filter at each time step using the magnitude of the fluctuation coefficient includes: If the fluctuation coefficient is greater than or equal to a preset threshold, the order of the Butterworth filter is set to a first value; otherwise, the order of the Butterworth filter is set to a second value, wherein the first value is greater than the second value.

8. The method for dynamic load control of transmission lines applicable to high-voltage transmission systems as described in claim 1, characterized in that, The current compensation based on harmonic components includes: At each time point, a compensation current with equal amplitude but opposite phase to the extracted harmonic current components is input into the power grid based on pulse width modulation technology to complete the current compensation.

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